gallberryEnglishOxford New American Dictionarygallberry /ˈɡôlˌberē, ˈɡɔlˌbɛri / (also gallberry holly) ▸ noun (plural gallberries) a North American holly with shiny leaves and white flowers. Genus Ilex, family Aquifoliaceae: the tall gallberry (I. coriacea) of the southeastern US, and the more widespread low gallberry (I. glabra), with black berries and nearly spineless leaves.